A coated-wire ion selective electrode based on zinc(II) acetylacetonate as ionophore exhibited linear response with Nernstian slope of -59.6 ± 1.0 mV/decade over a wide concentration range (1.0<FONT FACE=Symbol>´</FONT>10-5-1.0<FONT FACE=Symbol>´</FONT>10-1 mol L-1). This electrode has 5.0<FONT FACE=Symbol>´</FONT>10-6 mol L-1 detection limit. The proposed electrodes has a response time between 5-10 s to achieve a 95% steady potential for salicylate concentrations. The electrode was suitable for use in aqueous solutions in a wide pH range of 2.7 to 7.8. The electrode life time was tested over a period of two months to investigate its stability. No significant change in the performance of the electrode was observed during this period, but after two months, a gradual decrease ocurred in the slope. The proposed electrode showed high selectivity for salicylate over a number of common inorganic and organic anions. The electrode was successfully applied to the determination of salicylate in pharmaceutical samples.
coated wire salicylate-selective electrode; salicylate; zinc(II) acetylacetonate
